Figures (8)

Computed intensity of THz radiation after a wire-grid THz polarizer versus the polarizer angle (vertical axis) and ω to 2ω phase ψ (horizontal axis). Azimuthal angle θ of BBO crystal and the 2ω polarization is 55° in respect to polarization of the ω beam. The pump beam energy is 800 μJ per pulse. The 90° on the vertical axis corresponds to polarization of the ω beam. γ=1.96, ϵ=0.16.

Measured intensity of the 391.4 nm fluorescence band head at three different points of the plasma string versus the BBO crystal position, i.e., the ω to 2ω phase ψ. The beam focus position in this scale is at −135mm.

Measured intensity of THz radiation after a wire-grid THz polarizer versus the polarizer angle (vertical axis) and ω to 2ω phase ψ (horizontal axis). Azimuthal angle θ of BBO crystal is 55° in respect to polarization of ω beam. The pump beam energy is 400 μJ per pulse. The 90° on the vertical axis corresponds to polarization of the ω beam.

Image of a THz radiation pattern captured at 9.1 mm behind the focal plane of a parabolic mirror by a microbolometer detector array. The ring-shaped image demonstrates that the THz pulse is directed into a cone with a 19° opening angle.